The Mission First Tactical TEKKO polymer AK47 Integrated Rail System was announced just prior to the 2013 SHOT Show and we were able to grab some photos of them. There are two versions made of polymer: the TP47IRS and the TP47LIRS.
Pricing runs from $39.99 for just the lower rail with three Picatinny rails to $69.99 for the four rail system. The rails feature simple installation (read: no gunsmithing!) and are 922R compliant for firearms importion regulation purposes. The side rails are short rails on both, while the upper and lower rails are full length.